Entomopathogens for control of Asian longhorned beetles (Coleoptera: Cerambycidae)

Asian longhorned beetles, Anoplophora glabripennis (Motschulsky) (ALB), are native to China and Korea but invasive populations now threaten hardwood forests in North America and Europe where eradication is the main tactic. In North America, invasive ALB were first found in the New York City area in 1996 and, since then, infestations were detected in 5 additional states. Beginning in 1998, studies of fungal entomopathogens for ALB control were begun, followed by studies with entomopathogenic nematodes, Bacillus thuringiensis Berliner, and microsporidia. Studies with entomopathogenic fungi initially focused on a commercialized method used for application of Beauveria asiatica against adult cerambycids in Japanese orchards: cerambycids walk across bands covered with infective spores of entomopathogenic fungi that are attached around trees. For use in the United States, Metarhizium brunneum Petch F52 was grown in fungal bands and tested against adult ALB in US quarantine labs as well as in the field in China. Fungal infection reduced female longevity, fitness, and flight. Long-lived M. brunneum microsclerotia formulated in hydromulch were investigated as an alternative application method. Several species of entomopathogenic nematodes applied to ALB emergence holes showed promise for infecting and killing ALB larvae. The pathogens that have been investigated and developed are considered part of the arsenal of methods for ALB control and not "stand-alone" tactics. While no pathogens have been used operationally in the United States, information gained about these pathogens is available and could be used as situations warrant more tools for managing ALB.